We will study three enzymes that metabolize kinins and angiotensins. Carboxypeptidase N, kininase I that inactivates bradykinin will be purified and the biological activity of its subunits as well as their fate in the body will be studied. The second enzyme is kininase II or angiotensin I converting enzyme. This enzyme will be isolated from kidney and the properties of the membrane-bound enzyme as well as its inhibition will be investigated. Prolylcarboxypeptidase or angiotensinase C inactivates angiotensin II. We will develop a sensitive assay for this enzyme and study its distribution in the body and its excretion in urine.